Viewport: Exposing SetNextWindowViewport(). Used in demo and old/obsolete SetNextWindowPosCenter() (which is an interesting case). Fixed back-end likely crash calling GetFocus() after viewport destruction. Fixed metrics crash.

Viewport, Platform: Refresh monitor list (win32, glfw) + avoid calling GetWindowFocus before platform window creation to not require of backend to null-check things inconsistently. (#1542)

Viewport: Removed unnecessary fields (now that the coordinate system is consistent accross viewports): MouseRefPrevViewport, MouseClickedPosViewportId. (#1542)

Viewport, Platform: Using Platform_GetWindowFocus to provide a much stronger heuristic of platform z-order, in replacement for when the back-end cannot provide io.MouseHoveredViewport. The pressure for it to work well increased with the use of viewports by popups/menus. (#1542)

Misc: tweaks + minor changes merged from master to reduce branch drift. Removed code that ended up unused.

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp
#	imgui.h
#	imgui_internal.h

Misc: Comments and shallow/small changes (merged from viewport branch to minimize branch drift).

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/allegro5_example/imgui_impl_a5.cpp
#	examples/allegro5_example/imgui_impl_a5.h
#	examples/allegro5_example/imgui_impl_allegro5.cpp
#	examples/allegro5_example/imgui_impl_allegro5.h
#	examples/allegro5_example/main.cpp
#	examples/imgui_impl_allegro5.cpp
#	examples/imgui_impl_allegro5.h
#	imgui.cpp
#	imgui_internal.h

Internals: Removed unecessary Pos/PosFloat separation, only reason appears to be mostly pre-1.0. The only piece of code that I expected sub-pixel window position to matter actually already round its delta (wrongly so, will fix later/separately if we want).

Viewport: Tidying up AddUpdateViewport() calls. Moved flags argument. Removed extraneous mid-frame call to FindPlatformMonitorFromRect(). (#1542)

Viewport: Fixed issues with popups drifting in particular when reference mouse position become invalid (e.g. changing app focus while viewported-menu is open). Storing monitor index in viewport at beginning of the frame. (#1542)

Internals: Removed misleading ImRect::FixInverted + fix minor formatting in Readme. ...

Demo: Fixed Overlay: Added a context menu item to enable freely moving the window.

Viewport, Platform: Fixed IME positioning for multi-viewport. Moved API from ImGuiIO to ImGuiPlatformIO. Because it is extremely unlikely to people redefined this API manually the moving-forward-breakage is ok. (#1542) ...

SDL2 ime support under Win32 never worked properly because of SDL interferences.

Viewport: Switched to using unified platform-absolute mouse coordinates, which simplify lots of problems and simplify/reduce tricky conversions, makes ImVec2 less ambiguous. Fixed various viewport/windowing/popups/synchronization bugs. Settings on host-viewport are stored as relative (made settings decently compatible between viewport enable/disabled settings). Merged ImGuiViewport::Pos and ::PlatformPos. Tweaked thumbnails. Better, smaller code. (#1542)

Viewport: WIP for Tooltips, Popups, Menus to create their own viewport. Resizing a window allows it to leave the main viewport. (#1542)

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_dx10.cpp
#	examples/imgui_impl_dx11.cpp
#	examples/imgui_impl_dx12.cpp
#	examples/imgui_impl_dx9.cpp
#	examples/opengl2_example/imgui_impl_glfw_gl2.cpp
#	examples/opengl3_example/imgui_impl_glfw_gl3.cpp
#	examples/sdl_opengl2_example/imgui_impl_sdl_gl2.cpp
#	examples/sdl_opengl3_example/imgui_impl_sdl_gl3.cpp
#	examples/vulkan_example/imgui_impl_glfw_vulkan.cpp
#	imgui.cpp
#	imgui_internal.h

BeginMainMenuBar: Followup to 1e41bad9. Removed public window flag. DisplaySafeAreaPadding defaults to (3,3) instead of (4.4). Comments, tab to spaces, Changelog. (#1439)

Added DisplaySafeAreaPadding to MainMenuBar height and fixed starting x position. Fixes main menu bar problems with TVs. (#1439)

Viewport: Fixed manual mouse resize to handle mouse viewport change, which will allow resizing a window while it changes viewport. Releasing manual resize may merge a window. Added ConvertViewportPosToViewportPos() helper. Renamed NewFrameUpdateMovingWindowDropViewport() to UpdateTryMergeWindowIntoHostViewport() and removed the now-unnecessary half of the function. + renaming (#1542)

Viewport: Comments, tweaks, renaming. Removed unnecessary stuff. Fixed zealous Clang warning. (#1542)

Viewport: Moved ImGuiWindowFlags_FullViewport to an internal ViewportOwned flag. Renamed AddViewport to AddUpdateViewport. (#Viewport: Shuffled code in Begin to reset size of reappearing popups prior to selecting viewport, to avoid mistakenly using an old size. Moved code out of UpdateSelectWindowViewport() to the section of Begin where positions is being locked down, to avoid code in-between duplicating this. (#1542))

Viewport: Virtual mouse position are patched immediately when viewports are moved in the virtual space, avoiding interaction glitchs on a resizing frame. (#1542)

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp
#	imgui_internal.h

Viewport: per-viewport overlay draw list created on demand. With this pattern it'll be easier to consider adding more (e.g. background draw list). (#545)

Internals: Window: Aggregating ImDrawList into the ImGuiWindow structure.

Viewport: Merged ImGuiPlatformData into ImGuiPlatformIO. Comments. (#1542)

Internals: Renamed GetFrontMostModalRootWindow() to GetFrontMostPopupModal() and exposed in imgui_internal.h (#1738)

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_dx10.cpp
#	examples/opengl2_example/imgui_impl_glfw_gl2.cpp
#	examples/opengl3_example/imgui_impl_glfw_gl3.cpp
#	examples/vulkan_example/main.cpp
#	imgui.h

Version 1.61 WIP

Version 1.60